Recently, research on hydrophilic/oleophobic surfaces has been increasing. Hydrophilic/oleophobic surfaces can be used in oil-repellent anti-fogging and water/oil separation applications. Especially, thickness control of the hydrophilic/oleophobic film is important for the water/oil separation. In this study, layer-by-layer(LbL) films of polyelectrolytes and SiO₂ nanoparticles were fabricated followed by adsorption of fluorinated surfactant and SiO₂ nanoparticles mixture to produce hydrophilic/oleophobic surfaces. The wetting properties of the films were investigated as a function of LbL films thickness. As the film thickness increased, the oil contact angle decreased significantly while water contact angle remained largely unchanged. To address this issue, another LbL film was first deposited to increase the film thickness, followed by depositing the hydrophilic/oleophobic LbL films. As a result, we could prevent the degradation of oleophobicity with the increase in the film thickness. Furthermore, analysis showed that the decrease in oil contact angle with increasing thickness of the hydrophilic/oleophobic film is associated with the reduced adsorption of the fluorinated surfactant and surface morphologies of the films.

The mean-variance optimization is subject to the instability of covariance matrix inversion, leading to extreme asset weights and poor out-of-sample performance. Hierarchical clustering-based approaches that do not require matrix inversion have been proposed as alternatives. This study employs a hierarchical equal-weight portfolio, a variant of Hierarchical Risk Parity that replaces inverse-variance weighting with equal allocation, to isolate the effect of hierarchical cluster structure on portfolio diversification. Using 29 stocks from the Dow Jones Industrial Average, four linkage methods-single, complete, average, and Ward-are compared in terms of dendrogram structure and out-of-sample performance. The results show that single linkage produces a step-like dendrogram with the highest volatility (14.50%) and the lowest Sharpe ratio (1.67). Average linkage achieves the highest Sharpe ratio (2.38) and the smallest maximum drawdown (-4.94%), while Ward's method delivers a Sharpe ratio (2.34) nearly identical to the equal-weight benchmark (2.33) with improved volatility and downside risk. Complete linkage exhibits the lowest volatility (9.56%) but also the lowest return. These findings suggest that hierarchical clustering-based portfolios can mitigate downside risk relative to equal-weight allocation, and that the choice of linkage method is a critical determinant of portfolio outcomes.

The objective of this study is to analyze the effects of site factors and economies of scale on forest operation costs by type of activity. The dataset comprises stand level site conditions, forest conditions, and operation costs for projects directly managed by the Forestry Cooperative over a five year period from 2021 to 2025. The analysis revealed that the cost was highest for reforestation, followed by harvesting. According to the regression analysis, the explanatory power of the models for forest operations excluding vine removal and commercial thinning was found to be less than 0.5 however, the variables used in the analysis demonstrated statistical significance. In terms of marginal costs, an increase of 1 meter in the distance to the site resulted in an increase of 112,400 KRW/ha for reforestation and 2,100 KRW/ha for harvesting. Furthermore, it was observed that as the operation area increased, the cost decreased due to economies of scale. Specifically, this cost reduction amounted to 456,200 KRW/ha for reforestation and 416,700 KRW/ha for harvesting. Additionally, steeper terrain led to higher operational costs a 1° increase in slope resulted in a total cost increase of 580,400 KRW/ha. Notably, commercial thinning costs rose by 456,700 KRW/ha, indicating that harvesting operations are highly sensitive to slope gradient. These findings suggest that harvesting should be restricted in stands exceeding a certain slope threshold, or otherwise conducted through spatial intensification to leverage economies of scale. The results also underscore the necessity of establishing adequate forest roads during harvesting to ensure sustainable utility for subsequent silvicultural operations, including reforestation.

This study was conducted to identify the level of major selection confidence and professional identity perception among health-related college students and to examine the factors influencing professional identity perception. The participants were 314 health-related college students enrolled at universities in Gyeongsangnam-do, Republic of Korea, who voluntarily agreed to participate after being informed of the purpose of the study. Data were collected using a structured questionnaire consisting of eight items measuring major selection confidence and eight items measuring professional identity perception. All items were rated on a 5-point Likert scale. Data were analyzed using descriptive statistics, Pearson's correlation analysis, independent t-test, one-way ANOVA with Duncan's post-hoc test, and multiple linear regression analysis using SPSS Statistics 29.0. The results showed that the mean score for professional identity perception was relatively high (M=4.08), while the mean score for major selection confidence was above average (M=3.87). Pearson's correlation analysis revealed a significant positive correlation between major selection confidence and professional identity perception (r=.784, p<.001). Significant differences in both major selection confidence and professional identity perception were found according to age, department, and academic year. Multiple linear regression analysis indicated that major selection confidence (𝛽=.774, p<.001) and department (𝛽=-.204, p=.032) were significant predictors of professional identity perception. The explanatory power of the regression model was 63.7% (R²=.637, Adjusted R²=.629). These findings suggest that major selection confidence is a key factor influencing the development of professional identity perception among health-related college students. Therefore, universities should provide systematic career guidance programs and educational interventions that support students' major adaptation and strengthen their professional identity perception.

High-manganese steel (including Hadfield steel) is a class of advanced alloys containing a high concentration of manganese (Mn), which enables the simultaneous achievement of high strength, excellent ductility, and superior wear resistance. Owing to its fully austenitic microstructure, high-manganese steel exhibits a relatively low fatigue crack propagation rate. Furthermore, under cyclic loading, localized strain-induced work hardening occurs, which contributes to enhanced resistance to fatigue damage and, consequently, an extended fatigue life. Nevertheless, welded joints are inherently susceptible to the presence of defects and microstructural heterogeneities, which may significantly deteriorate fatigue performance. In this study, recognizing the potential degradation of fatigue performance in welded joints of high-manganese steel, a systematic investigation was conducted to quantitatively evaluate the fatigue characteristics of weldments. Specifically, the fatigue crack propagation behavior of gas metal arc welded (GMAW) high-manganese steel was examined. Compact tension (CT) specimens were prepared from the welded joints for fatigue crack propagation testing. The results showed that, during the early stage of fatigue cycling, crack growth was negligible despite an increase in the number of cycles. As fatigue cycling progressed, stable crack propagation was observed, followed by a transition to a final stage characterized by a rapid acceleration in crack growth rate leading to fracture.

This study aims to derive a direction for rural youth housing planning by analyzing the architectural planning characteristics and preferences of the winning designs from a design competition aimed at improving the housing environment for young people in rural areas. The research method consisted of a case study applying four analytical frameworks to the winning designs of the rural youth housing design competition, and a preference survey targeting university students who wish to live in rural areas. The analysis results showed that the local government-sponsored youth housing project showed relatively high evaluations in community-oriented spatial composition elements such as relationships with public spaces, functional complexity, layout and movement lines, and composition of intermediate spaces. In addition, the external and intermediate spaces also showed planning characteristics centered on spatial systems and climate response. The Ministry of Agriculture, Food and Rural Affairs-sponsored youth housing project showed high preference in regional and environmental response elements such as independence and comfort of residential units, revitalization of external spaces and connection to the natural environment, reflection of regional context, and eco-friendly strategies. While the local government-sponsored youth housing project showed strengths in community-oriented spatial composition and establishment of external and intermediate space systems, the Ministry of Agriculture, Food and Rural Affairs-sponsored project showed planning characteristics that emphasized independent residential environments and reflection of natural and regional contexts. This study is significant in that it systematizes the architectural planning elements of rural youth housing and empirically presents differences in spatial strategies by policy type.

This study aimed to examine the level of major performance confidence among health-related college students and to identify differences according to general characteristics as well as the factors influencing major performance confidence. A descriptive cross-sectional design was employed, and data were collected from 314 students using a structured questionnaire. The data were analyzed using SPSS version 29.0, including descriptive statistics, independent t-tests, one-way ANOVA with Duncan post hoc tests, and multiple linear regression analysis. The results revealed that the mean score of major performance confidence was 3.76±0.65. Significant differences were found according to age (F=2.610, p=.036) and academic year (F=5.014, p=.007). Multiple linear regression analysis showed that the model was statistically significant (F=2.040, p<.05), although the explanatory power was relatively low (R² =.038, Adj. R² =.020). Department (β=-.449, p=.003) and academic year (β=-.441, p=.010) were identified as significant predictors. These findings suggest that major performance confidence is influenced by both individual and educational factors, highlighting the need for tailored educational programs and grade-specific strategies.

This study developed and validated a ConvLSTM (Convolutional Long Short-Term Memory)-based bathymetry prediction model tailored for the complex and non-stationary environment of the Nakdong River estuary. Periodic bathymetric survey data from 2013 to 2022 were synthesized into a 5 m grid-based spatiotemporal matrix, which was then applied to two distinct study sites: Area A (shallow waters, 18 surveys) and Area B (deep waters, 17 surveys). By integrating convolutional operations with an LSTM architecture, the ConvLSTM model was designed to simultaneously learn temporal dependencies and spatial correlations. Using 5D tensor inputs, the model effectively captured seasonal patterns and inter-grid relationships. Validation results demonstrated high predictive accuracy: Area A achieved an R² of 0.891, RMSE of 37.3 cm, MAPE of approximately 10.00 %, and KGE of 0.871; Area B reached an R² of 0.957, RMSE of 39.7 cm, MAPE of 5.52 %, and KGE of 0.937. The ConvLSTM model exhibited a distinct advantage in reproducing localized erosion and sedimentation patterns, particularly at sandbar boundaries and narrow channels. In the 2023-2030 projections, the model detailed spatiotemporal variations in the short-to-medium term; however, a plateauing effect due to the autoregressive structure was observed in long-term forecasts. This research confirms the practical utility of ConvLSTM for localized estuarine management, such as dredging planning and disaster response, and suggests the future necessity of integrating physical variables and developing hybrid models.

This study aimed to investigate the level of major selection certainty among health-related college students and to identify factors influencing it. A descriptive cross-sectional survey was conducted with 314 students enrolled in health-related majors at a university in the Gyeongnam region. Data were collected using a structured questionnaire consisting of eight items measuring major selection certainty on a 5-point Likert scale. The collected data were analyzed using SPSS version 29.0, including descriptive statistics, independent t-tests, one-way ANOVA with Duncan post hoc tests, and multiple linear regression analysis. The results showed that the overall mean score of major selection certainty was 3.87±0.695, indicating a moderate to above-average level. Significant differences were found according to age (F=4.318, p<.01), major (t=3.33, p<.001), and academic year (F=11.829, p<.001), with second-year students and emergency medical technology majors showing higher levels of certainty. Multiple regression analysis revealed that major (β=-.647, p<.001) and academic year (β=-.496, p<.01) were significant predictors of major selection certainty, although the explanatory power of the model was relatively low (Adjusted R²=.055). These findings suggest that major selection certainty is influenced by both academic and contextual factors but cannot be sufficiently explained by demographic variables alone. Therefore, it is necessary to develop tailored educational and counseling programs that enhance major satisfaction and career decision-making self-efficacy. Future studies should include broader psychological variables and more diverse samples to improve explanatory power and generalizability.

This study aimed to investigate the chemical composition of commercially available denture adhesives using gas chromatography-mass spectrometry (GC-MS). Five denture adhesive samples (Sample A-E) were analyzed under identical conditions, and volatile as well as low-molecular-weight organic compounds were qualitatively identified based on mass spectral library matching. The total ion chromatograms (TIC) showed that major peaks were distributed within the retention time range of approximately 6-23 min, with relatively higher intensities observed in the 10-15 min region across all samples. Major detected compounds included alkanes such as hexadecane and octadecane, and esters such as ethyl palmitate and butyl stearate, while alcohols and aromatic compounds were detected at relatively lower levels. Comparative analysis indicated that all samples exhibited similar overall chemical profiles, with alkane compounds being the predominant group, followed by esters and alcohols. Although the general compositional patterns were comparable, differences in the relative distribution of certain compound groups were observed among samples. These findings suggest that denture adhesives may share a common chemical basis while exhibiting variations in composition potentially related to formulation differences. However, as this study was conducted based on qualitative analysis, the results are limited to the identification and relative distribution of compounds, and do not provide quantitative information. Within these limitations, the present study provides fundamental information on the chemical characteristics of denture adhesives and may provide fundamental data for further quantitative and safety-related investigations.

This study aims to evaluate the clinical efficacy of Chest Compression-Synchronized Ventilation (CCSV) and to propose a policy roadmap for its integration into the South Korean emergency medical system. A mixed-method research design was employed, combining a comprehensive literature review with in-depth interviews of seven experts, including emergency physicians and first-class emergency medical technicians. The results indicate that CCSV enhances the thoracic pump mechanism through the formation of an 'air cushion' and maximizes venous return during the decompression phase. According to the SYMEVECA Phase 2 data, CCSV significantly improved outcomes in the shockable rhythm subgroup compared to Bag-Valve Mask (BVM) ventilation, more than doubling both the survival-to-discharge rate (45.2% vs. 21.9%, p=.02) and favorable neurological outcomes (41.9% vs. 20.5%, p=.02). Additionally, a significant increase in arterial oxygen partial pressure (PaO₂) of 76.1 mmHg was observed within 10 minutes of application (p=.026). Based on these findings, the study proposes key policy alternatives: institutionalizing advanced airway management, clarifying the legal scope of practice for paramedics, standardizing ambulance equipment, and establishing data-driven feedback systems. In conclusion, CCSV is a vital clinical intervention that can significantly enhance survival rates for out-of-hospital cardiac arrest patients and lead to a qualitative leap in the national emergency medical infrastructure.

This study aimed to examine the levels of emergency response performance confidence, professional self-concept, and major performance confidence among health-related college students and to identify the effects of emergency response performance confidence on professional self-concept and major performance confidence. The participants were 314 health-related college students enrolled in universities located in Gyeongsangnam-do, Korea. Data were collected using a structured questionnaire and analyzed using IBM SPSS Statistics 29.0. Descriptive statistics, independent t-tests, one-way ANOVA, Pearson's correlation analysis, and multiple regression analysis were conducted. The results showed that the mean scores were 3.88±0.69 for emergency response performance confidence, 4.02±0.69 for professional self-concept, and 3.76±0.65 for major performance confidence. Emergency response performance confidence was positively correlated with professional self-concept (r=.784, p<.01) and major performance confidence (r=.553, p<.01). In addition, professional self-concept was positively correlated with major performance confidence (r=.609, p<.01). Multiple regression analysis revealed that emergency response performance confidence (β=.196, p=.004) and major performance confidence (β=.445, p<.001) significantly influenced professional self-concept. Furthermore, emergency response performance confidence (β=.619, p<.001) and professional self-concept (β=.284, p<.001) were significant predictors of major performance confidence. These findings suggest that emergency response performance confidence is an important factor influencing both professional self-concept and major performance confidence among health-related college students. Therefore, educational programs that strengthen first aid practice, cardiopulmonary resuscitation (CPR) training, and simulation-based learning are needed to enhance emergency response performance confidence and promote professional identity and major-related competencies.

The quotation process in small and medium-sized valve manufacturing enterprises has long relied on manual, Excel-based workflows, resulting in processing times of 15 to 30 minutes per quotation, error rates of 10 to 15%, and significant opportunity costs from delayed orders. The complexity of valve specifications - spanning over 75,000 possible combinations of product category, model, size, material, and pressure rating - further compounds these inefficiencies by requiring highly experienced personnel for accurate quotation generation. To address these challenges, this study designs and implements an AI-CPQ(Artificial Intelligence Configure-Price-Quote) Agent based on a four-phase AI orchestration framework integrating Large Language Model(LLM) and Retrieval-Augmented Generation(RAG) technologies. The proposed pipeline consists of four sequential phases: Phase 1 extracts structured information from unstructured inputs such as PDFs and natural language; Phase 2 normalizes heterogeneous material expressions into standardized product codes using an advanced LLM; Phase 3 retrieves matched products and calculates final prices via RediSearch and Fuzzy Matching across 924 products and 435 companies; and Phase 4 enables real-time conversational quotation refinement through Tool Use(Function Calling). The complete automated pipeline is processed within approximately three minutes. The proposed system establishes a new paradigm shifting from Excel-based to AI-driven quotation automation for small and medium-sized manufacturers.

This study aimed to investigate the level of public service motivation among health-related college students and to identify differences according to general characteristics as well as influencing factors. A descriptive survey design was employed, and the participants consisted of 314 students enrolled in universities located in the Gyeongnam region. Data were collected using a structured questionnaire and analyzed using SPSS version 29.0. Statistical analyses included frequency, percentage, mean, standard deviation, independent t-test, one-way ANOVA with Duncan post-hoc test, and multiple linear regression analysis. The results showed that the mean score of public service motivation was 3.81±0.699, indicating a moderate to high level overall. Significant differences in public service motivation were observed according to age, department, and academic year. In particular, students in the emergency medical technology department showed significantly higher levels of public service motivation compared to students in the biomedical health-related department. In the multiple regression analysis, department was identified as the only significant predictor of public service motivation, whereas gender, age, religion, academic year, and having a family member in the medical field were not statistically significant factors. The explanatory power of the regression model was relatively low, suggesting that public service motivation is a complex construct influenced by various psychological, educational, and social factors. These findings indicate that public service motivation among health-related college students differs according to certain general characteristics, particularly academic major. Therefore, it is necessary to develop educational programs and curricula tailored to the characteristics of each major in order to strengthen public service motivation and encourage its translation into actual professional and social behaviors.

This study evaluated the hair loss improvement potential of Saccharina japonica (kelp) extract fermented with Alteromonas marina, distributed by the Korean Culture Center of Microorg anisms (KCCM). The proximate composition showed that ash content was highest in the fermented extract powder (38.8 g/100g), and carbohydrate content decreased from 58.7 to 39.1 g/100g compared to water extract powder, suggesting polysaccharide degradation by A. marina; however, the molecular weight and structure of the fermentation products were not directly characterized in this study. The fermented extract showed markedly elevated total flavonoid content (15.4 mg QE/g ,~38.5-fold vs. water extract) and DPPH / ABTS EC₅₀ values of 4.3/5.8 mg/mL. Cytotoxicity assays confirmed no toxicity to human dermal fibroblasts (HDF), RAW 264.7 macrophages, or B16F10 melanoma cells at tested concentrations. In LPS-stimulated RAW 264.7 cells, the fermented extract suppressed NO (~70%), TNF-α (~61%), and IL-6 (~55%) at 200 ㎍/mL (p<0.001). In α-MSH-stimulated B16F10 cells, melanin content and tyrosinase expression were reduced to levels comparable to arbutin at 200 ㎍/mL. In TNF-α-stimulated HDF cells, the fermented extract (50, 100 ㎍/mL) significantly suppressed IL-6, IL-1β, and TNF-α gene expression and partially restored antioxidant g ene expression (CAT, SOD, GPx). Wound healing assays demonstrated dose-dependent promotion of HDF cell migration, with 100 ㎍/mL achieving the fastest closure rate (slope 0-12 h:~6.2 %/h) and shortest T50 (~7.8 h). These results suggest that A. marina-fermented S. japonica extract is a promising functional cosmetic material candidate for improving the scalp environment, indicating its potential for hair loss prevention. However, direct validation using dermal papilla cells or animal models is warranted.

This study aimed to examine the level of meaning in life and its influencing factors aThis descriptive study was conducted to investigate the level of meaning in life among health-related college students and to identify factors influencing it. The results showed that the overall level of meaning in life was above average, with a mean score of 3.65. Significant differences were observed according to academic major (p<.01), with students in the Department of Emergency Medical Technology reporting the highest level of meaning in life (M=3.88), whereas students in the Department of Companion Animal Studies reported the lowest level (M=3.21). In addition, significant differences were found according to experiences of the death of significant others (t=5.461, p<.05), with students who had not experienced the death of a significant other reporting higher levels of meaning in life. Multiple regression analysis revealed that academic major (β=-.478, p<.01) and experience of the death of significant others (β=.223, p<.01) were significant predictors of meaning in life. The explanatory power of the model was 17.4% (Adjusted R²=.174). These findings suggest that meaning in life among health-related college students is influenced by both educational characteristics and personal life experiences. The results of this study highlight the need for educational and counseling programs that support the development of meaning in life and psychological well-being among health-related college students. Future studies should incorporate a broader range of psychological and social variables to develop more comprehensive models explaining the formation of meaning in life.

Copper is one of the rare metals of the metallic elements present in nature that exists in a pure form that is readily available without smelting and is known to cause acute and chronic poisoning in the event of addiction. Cobalt is often used for cigarettes, batteries, colors, and pigments. It can cause symptoms such as myocardial disease, peripheral neuropathy, hypothyroidism, sensory neuropathy on both sides, blindness on both sides, and so on. One of methods of removing these metals is biosorption using biomass. In South Korea, large amounts of jujube shell as by-products are produced from food industries. However, most of these by-products exist with no disposal options. Objective of this research was carried out to investigate the removal effect of heavy metals (Cu²⁺, Co²⁺) in aqueous solution using jujube as adsorbents. We experimented on the effect of sample amount on the removal efficiency for sample solution. As a result, 74.3% of cobalt and 97.15% of copper were removed at most. Considering economic efficiency, the cobalt removal efficiency was optimal at an adsorbent mass of 0.4 g, while the copper removal efficiency was highest at 0.2 g.

This study aimed to assess the level of emotional burnout experienced by healthcare students and analyze the key factors contributing to it. The study was conducted with 183 healthcare students enrolled in a university located in the Gyeongnam area, using a descriptive survey research method. Data were collected through a questionnaire, and emotional burnout was measured using a 5-point Likert scale. The data were analyzed by calculating the mean and standard deviation, and differences according to general characteristics were examined using independent t-tests and one-way analysis of variance (ANOVA). The results showed that the overall level of emotional burnout among healthcare students was 1.95 (SD=0.96). According to gender, female students experienced a higher level of emotional burnout (mean=2.02, SD=0.73) compared to male students (mean=1.77, SD=0.82) (t=4.392, p<.05). By department, students from the Department of Companion Animal Science experienced the highest emotional burnout with a mean score of 2.41 (SD=0.89), followed by students from the Department of Biomedical Laboratory Science (mean=2.02, SD=0.63), the Department of Emergency Medical & Rescue Technology (mean=1.82, SD=0.80), and the Department of Biomedical and Health Sciences (mean=1.80, SD=0.57) (p<.01). Regarding academic year, first-year and second-year students experienced higher levels of emotional burnout, while fourth-year students had the lowest level with a mean score of 1.78. Multiple linear regression analysis revealed that department and academic year were significant factors influencing emotional burnout (F=3.707, p<.05), with an adjusted R² of 0.094. This study provides valuable baseline data on the level of emotional burnout experienced by healthcare students and its contributing factors, which can be used to develop tailored educational interventions to improve emotional health and well-being among healthcare students in the future.

This Study aimed to empirically examine the effects of advertising message framing on consumer responses to marine bio-cosmetics and to identify the sequential mediation pathways from ad credibility to purchase intention. Four advertising conditions were developed-an efficacy frame, an environment x positive frame, an environment x negative frame, and an integrated fraom-and an onlne experiment based on a within-subjects design was conducted with 500 participants. Repeated measures ANOVA and sequential mediation analysis using PROCESS macro Model 6 were employed. Results revealed that advertising frame type had a significant effect on an credibility, with the environment x negative frame eliciting the highest credibility. No significant differences were found across frame types for perceived authenticity, self-brand connection, or purchase intention. However, the sequential mediation path from ad credibility through perceived authenticity and self-brand connection to purchase intention was significant across all four frame conditions. Furthermore, full mediation was observed in the efficacy and integrated frame conditions, while partial mediation was found in the environmental appeal frame conditions, indicating the the nature of the mediation structure varies by frame type. These findings suggest that credibility-based environmental framing is an effective message strategy for marine bio-cosmetic advertising, offering theoretical and practical implications for sustainable advertising communication in the marine bio-cosmetics industry.

This study aimed to examine the level of depression among health-related university students and to identify differences according to general characteristics as well as factors influencing depression. A descriptive survey design was employed, and data were collected from 314 students using a structured questionnaire. Depression was measured using a 5-point Likert scale, and the collected data were analyzed using IBM SPSS Statistics. Descriptive statistics, independent t-tests, one-way ANOVA, and multiple regression analysis were conducted. The results showed that the overall level of depression was relatively low (M=1.73±0.69). Among the sub-items, behavioral and cognitive symptoms such as reduced concentration and decreased verbal interaction were relatively higher compared to emotional symptoms. In the analysis of differences according to general characteristics, a statistically significant difference was found only in one item related to reduced verbal interaction by gender, while other variables did not show significant differences. In the multiple regression analysis, although the overall model showed a high explanatory power (R²=.863), none of the individual independent variables were statistically significant. This suggests that demographic variables alone are insufficient to explain depression among health-related university students. In conclusion, although the overall level of depression was low, certain behavioral symptoms indicate the potential presence of a risk group. Therefore, early screening and intervention strategies focusing on mental health management are necessary.